/*
 * File      : completion.c
 * This file is part of RT-Thread RTOS
 * COPYRIGHT (C) 2012, RT-Thread Development Team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Change Logs:
 * Date           Author       Notes
 * 2012-09-30     Bernard      first version.
 */

#include <rthw.h>
#include <rtthread.h>
#include <rtdevice.h>

#define RT_COMPLETED    1
#define RT_UNCOMPLETED  0

void rt_completion_init(struct rt_completion* completion)
{
	rt_base_t level;
	RT_ASSERT(completion != RT_NULL);

	level = rt_hw_interrupt_disable();
	completion->flag = RT_UNCOMPLETED;
	rt_list_init(&completion->suspended_list);
	rt_hw_interrupt_enable(level);
}
RTM_EXPORT(rt_completion_init);

rt_err_t rt_completion_wait(struct rt_completion* completion,
                            rt_int32_t            timeout)
{
	rt_err_t result;
	rt_base_t level;
	rt_thread_t thread;
	RT_ASSERT(completion != RT_NULL);

	result = RT_EOK;
	thread = rt_thread_self();

	level = rt_hw_interrupt_disable();

	if(completion->flag != RT_COMPLETED) {
		/* only one thread can suspend on complete */
		RT_ASSERT(rt_list_isempty(&(completion->suspended_list)));

		if(timeout == 0) {
			result = -RT_ETIMEOUT;
			goto __exit;
		} else {
			/* reset thread error number */
			thread->error = RT_EOK;

			/* suspend thread */
			rt_thread_suspend(thread);
			/* add to suspended list */
			rt_list_insert_before(&(completion->suspended_list),
			                      &(thread->tlist));

			/* current context checking */
			RT_DEBUG_NOT_IN_INTERRUPT;

			/* start timer */
			if(timeout > 0) {
				/* reset the timeout of thread timer and start it */
				rt_timer_control(&(thread->thread_timer),
				                 RT_TIMER_CTRL_SET_TIME,
				                 &timeout);
				rt_timer_start(&(thread->thread_timer));
			}

			/* enable interrupt */
			rt_hw_interrupt_enable(level);

			/* do schedule */
			rt_schedule();

			/* thread is waked up */
			result = thread->error;

			level = rt_hw_interrupt_disable();
		}
	}

	/* clean completed flag */
	completion->flag = RT_UNCOMPLETED;

__exit:
	rt_hw_interrupt_enable(level);

	return result;
}
RTM_EXPORT(rt_completion_wait);

void rt_completion_done(struct rt_completion* completion)
{
	rt_base_t level;
	RT_ASSERT(completion != RT_NULL);

	if(completion->flag == RT_COMPLETED)
		return;

	level = rt_hw_interrupt_disable();
	completion->flag = RT_COMPLETED;

	if(!rt_list_isempty(&(completion->suspended_list))) {
		/* there is one thread in suspended list */
		struct rt_thread* thread;

		/* get thread entry */
		thread = rt_list_entry(completion->suspended_list.next,
		                       struct rt_thread,
		                       tlist);

		/* resume it */
		rt_thread_resume(thread);
		rt_hw_interrupt_enable(level);

		/* perform a schedule */
		rt_schedule();
	} else {
		rt_hw_interrupt_enable(level);
	}
}
RTM_EXPORT(rt_completion_done);

